On Thu, Aug 08, 2019 at 12:07:28PM -0700, Linus Torvalds wrote: > End result: a DRAM buffer can work, but is not "reliable". > Particularly if you turn power on and off, data retention of DRAM is > iffy. But it's possible, at least in theory. > > So I have a patch that implements a "stupid ring buffer" for thisa > case, with absolutely zero data structures (because in the presense of > DRAM corruption, all you can get is "hopefully only slightly garbled > ASCII".
Note that you can hook this into printk as a fake early serial device; just have the serial device write to the DRAM buffer.
